Personal hydration systems are known in the art and are used extensively by people that are active in sports, trekking activities, recreational is activities as well as in the military. Over the last decade, people in general and especially people that are active in physical activities became aware of the fact that drinking during physical activity is crucial from health considerations. Therefore, personal hydration systems were developed over the years and since the use of soft polymers such as polyurethane became applicable in designing the drinking containers of the hydration systems, flexible containers, bladder-like containers, became widely used. An example for a personal hydration system is shown in U.S. Pat. No. 5,816,457 “hydration system” by Croft, filed in 1996. This patented hydration system for backpackers or other athletes includes a bladder, a filling opening, an enclosing cover and filling opening, a flexible line and a deformable valve to be held in the user's mouth. Another hydration system was invented by the inventor of the present invention (Gill Yoram) and Ezer Asaf and disclosed in PCT patent application no. PCT/IL97/00263 (filed in the U.S. Ser. No. 09/297,384) “Flexible Container for Storing and Dispensing Liquids”. This flexible container comprises an inner bag and at least one outer bag, and liquid dispensing means.
One of the problems stemming from the use of flexible polymers in the design of hydration containers is that they are not easily cleaned. The soft polymer itself is a material that may absorb matter from the liquid, especially if the liquid filled in the container is juice or tea or other sugar containing liquid. In addition, the container is soft and has welded areas, therefore residues of the liquid that was inside the container may be left in corners formed in the sides of the container. Cleaning becomes a problem even when using the opening of the container from which the container is filled by liquid since this opening is usually relatively small. Accessories for cleaning flexible containers are available (can be purchased in the markets) but still, the maintenance of the container is difficult.
Most of the flexible containers are made from two flexible sheets of polymer welded together from all sides while an opening for filling the container and drinking from it is formed on the side of the container in the surface of one of the sheets. One of the solutions for the maintenance problem in those types of flexible containers is to leave a large opening on one of the sides of the container by leaving an unwelded area. It is straightforward that the unwelded area that acts as an opening is in the narrower side of the container while it becomes very easy to clean the interior of the container by inserting a hand into it. Moreover, it is easy to dry the container after cleaning is finished and there is no need for expensive cleaning and drying accessories.
Leaving an unwelded area to be used as an opening for cleaning the container brought about another problem. The ability to hermetically seal this opening when the container is in use and filled with liquid is diminished. Several solutions are available on the markets. Two of the solutions (“easy clean” from Blackburn company and another container from ultimate direction company) are based on an extended opening that may be folded several times and possibly to different directions. The folds of “easy clean” may be secured by hook and loop fastenrs. The solution of ultimate direction is based on U.S. Pat. No. 5,941,640 “Roll Top Bladder” by Thatcher filed in 1997. This bladder includes two sidewall portions, which are disposed opposite one another and joined along a majority of the perimeter. In the unattached portion, a neck is formed, which extends from the body of the bladder. To close the conduit formed by the neck portion, the neck portion is rolled towards the body. The rolled neck portion seals the opening closed and prevents liquid from escaping out of the neck. Another solution is offered by cascade designs company. Here, their platypus flexible hydration system is closed by a “big zip”. The closure is based on the idea of a plastic zipper in which one side of the opening is provided with a strip that protrudes from the sheet surface and opposite to the strip, a corresponding groove is provided. When the user wishes to close the container, he presses the strip into the groove so that the opening is closed. Another solution that is based on the idea of a ZIP-LOCK® is disclosed in U.S. Pat. No. 5,913,456 by Dileman “Pressurized Portable Drinking System” filed in 1997. This patent discloses a liquid dispenser that includes a container formed of a flexible synthetic resin material and a hose connected to the container for dispensing liquid. Among other features, the dispenser also includes a closure assembly that is positionable in a scaled position sealing a cavity shut beneath a mouth so that the cavity is substantially liquid tight, and an unscasled position exposing the cavity to the mouth for filling.
In all the available solutions including the above mentioned ones, the container is prone to liquid leakage. In all of these cases, the container has to be positioned so that the opening is in the upper side of the container at all times. This fact prevents the free use of the container to many of the application that these containers are designed for. For example, when the personal hydration system is placed on the rear of a bike, it is most convenient to put the container on its side. Placing a container having a cleaning opening closed in the way described herein above cause leakage and loses of liquid. Those containers may be used only when the container is hanged, a fact that limits the use of the personal hydration system. There is a need to provide an easy way to close the hydration container so that the container is completely sealed when in use. Moreover, when the container is safely sealed, it may be placed in any orientation without leakage. Another problem that originates from using a zip-like closure is that when the container is filled, the user has to squeeze the side edges of the container in order to open up the opening. This operation is uncomfortable.